In cigarette manufacturing and packing plants, a variable-capacity store, of the type described for example in Patent Application EP0738478, is interposed between a cigarette manufacturing machine and a packing machine to compensate for any difference between the number of cigarettes produced and the number of cigarettes packed.
The store described in Patent Application EP0738478 is a variable-capacity FIFO (First In First Out) store, i.e. in which the cigarettes fed first into the store are also the first to be fed out, so as to prevent the cigarettes from being parked too long in the store and so possibly losing their aroma.
More specifically, the store described in Patent Application EP0738478 comprises an input station and an output station arranged in series along a cigarette feed path; and an endless conveyor comprising a conveying branch, for conveying the cigarettes along the path, and a return branch, which respectively define a first and second coil of given lengths about respective pairs of drums. In use, the cigarettes are fed from the input station to the output station by the conveying branch, and a regulating member adjusts the lengths of the two branches in complementary manner to adjust the overall capacity of the store.
Variable-capacity stores of the type described above have proved practical, are therefore used widely in cigarette manufacturing and packing plants, and, being of considerable size but light in weight, are normally installed a given height (at least three meters) off the floor to make the best use of available floor space. Being installed so high off the floor, however, connecting the stores to an input conveyor (supplying the cigarettes to the input station) and/or to an output conveyor (receiving the cigarettes from the output station) can prove relatively complicated and expensive by calling for special vertical conveyors at the input and output stations to lift/lower the mass of cigarettes to/from the store.